Multipower-plant transmission for aircraft and the like



April 1930- J. D. VAN VLIET 1,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT IQND THE LIKE Filed Sept. 28;1925 ;5 Sheets-$heet 1 INVENTUW www- J. D. VAN VLIET 1,754,192

Filed Sept. 28, 1925 15 Sheets-Sheet 2 RNVENTOR II IROW h 51 H i i 5 H ix mu \m \m p N v m.) :5 h .i 0 g i w \w mm m mm 3 w, A T w m i 1 .1 M IA v I I m s. z w

April 8, 1930.

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE April 8, 1930. 7J. D. VAN VLIET 1,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE Filed Sept. 28.1925 15 Sheets-Sheet 3 m m m @6- INVENTOR April 1930. J. D. VAN VLIET1,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE Filed Sept. 28.1925 15 Sheets-Sheet 4 i n l, i 7 -i (5 5 I I) 95 INVENTOR April 8,1930. J. D. VAN VLIET 1,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE'LIKE Filed Sept. 28,1925 15 Sheefis-Sheet 5 INVENTOR April 8, 1930. J. D. VAN VLIET1,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE Filed Sept. 28.1925 15 Sheets-Sheet 6 April 8, '1930.- J. D. VAN VLIET 1,754,192

' MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE Filed Sept. 28,1925 15 Sheets-Sheet '7 INVENTOR April 8, 1930. J. b. VAN VLIET I1,754,192 MULTIPOWERPLANT TRANSMISS ION FOR AIRCRAFT AND THE LIKE FiledSept. 28, 1925 15 Sheets-Sheet 8 "7 ill :1"

I INVENTOR April 8, 1930. J. D. VAN VLIET 1,754,192

I MULTIPQWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE Filed Sept. 28.1925 15 Sheets-Sheet 9 396 i I i l I i g r 49 H' HE I I Pi: 4/5 3 :i :i:97 k a E 398 l.

13.. J. D, VAN vuET fifimsim MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFTAND THE LIKE Filed Sept. 28, 1925 15 Sheets-Sheet l0 INVENTOR April 8,1930. J, D. VAN VLIET 1,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAF T AND THE LIKE Filed Sept. 28,1925 15 ShetS-B-Sheet l1 INVENTOR April 8, 1930. I J. D. VAN VLIET1,754,192 MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE FiledSept. 28, 1925 '15 Sheets-Sheet -12 Fig. 28

April 8, 1930. J. D. VAN VLIET 1,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE Filed Sept. 28.1925 1 5 Sheets-Sheet l3 INVENTOR wxwk April 8, 1930. J. D. VAN VLIETMULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE 15 Sheets-Sheet14 Filed Sept. 28. 1925 e'l'ilnii VIII/I14 INVENTOR xhmsmhmv April J. D.VAN VLIET 13,754,192

MULTIPOWERPLANT TRANSMISSION FOR AIRCRAFT AND THE LIKE Filed Sept. 28.1925 15 Sheets- Sheer, 5

lllliillllil Patented Apr. 8, 1930 PATENT ormca JOHN HUMANS VAN VLIEZ L,OF SAN FRANCISCO, CALIFORNIA MULTIPOWER-PLANT TRANSMISSIQN' FOE,AIRCRAFT AND THE LIFE Application filed September at, 19%. Serial No.59,135.

' My invention relates to the. mechanical transmission of power from aplurality of powerplantsto a common shaft. The invention is especially,but by no means exclusive- 1y, applicable to flying machines equippedwith a plurality of englnes actuating a single propeller shalt.

Une oi the objects of the invention is to provide difi'erential meanswhereby the slowlo ing down or cutting out of one or more oi thepowerplants will not interfere with the normalfunctioning of theremaining ones.

Another object is to provide means whereby one or more engines can, atthe will of the operator, be instantly connected with or dis connectedfrom the common shaft.

A further object is to provide means whereby the transmission of powerfrom any combination of engines can be instantly 2 changed to that froma different combina tion, without this causing any appreciableirregularities in the rotative speed of the common shaft.

A still further object is to provide means whereby the implement ofpropulsion or locomotion adapts itself automatically to the powertransmitted.

A. still further object is to provide means whereby a reversal of thepropulsion means 80 can be efiected by the same'mechanism and-manipulation employed for the other operations.

A still further object of the invention is to provide means forautomatically throwing out of combination any defectively functioningpowerplant and automatically throwing in a reserve powerplant. The aboveand other objects of theinvention will be pointed out and fullydescribed in the annexed specification. v

A practical embodiment of the invention, comprising certain arrangementsand combinations, has been depicted in the accompanying drawings, but Iwish it to be explicitly understood that I do not limit myself to theseparticular designs and arrangements, since these may be greatly modifiedby amplification and adaptation to different kinds of vehicles, all ofsuch adaptations and modifications however, falling within the scope ofthe invention as covered by the appended claims.

Reference is to be had to i-the following drawings in which:

Fig. 1 shows a schematic layout of a multiple power-unit installed in anairplane and actuating an adjustable propeller.

Fig. 2 shows a compound difierential transmission, the top of the gearcase beingv broken awa and the gearing and shafting shown part y insection.

trol.

Fig. 4 is a section through Fig. 3 taken along the line M.

Fig. 5 is an explanatory diagram of the clutch control mechanism.

Fig. 6, Fig. 7, Fig. 8 and Fig. 9 are details of the-clutch controlmechanism.

Fig. 10 is an explanatory diagram pertaining to the clutch controlmechanism.

Fig. 3 shows a portion of the clutch con- Fig. 11 is a schematic view ofthe clutch control arresting device.

Fig. 12 is an elevation of the clutch control actuating mechanism.

Fig. 13 is a plan view of Fig. 12. Fig. 14, Fig. 15, Fig. 16 and Fig. 17are details of the clutchcontrol actuating mechanism. Fig. 181s aplan'view ofpart oi the propeller adjusting mechanism. Fig. 19 is asectional elevationof Fig. 18.

Fig. 20 is a front elevation of Fig. 18 and Fig. 30 is an explanatorydiagram show- 7 ing the transmission ratio for the automatic clutchcontrols.

.mission, the automatic clutch controls pluralit of powerplants can beemployed to great a vantage inasmuch as the power re- I quired forpropulsion or locomotion may vary considerably under differentconditions. In some instances a single powerplant may be sufiicient topropel the vehicle, whereas under different conditions it may beexpedient or even imperative to utilize the com bined power of allpowerplants available.

As an example of this alternative I would cite the case of the twinormultiple-screw steamship in which each screw is actuated b an individualengine. Maximum velocity is obtained by having engines turning at fullspeed, whereas steering and manoeuvering is eiiected by stoppin slowingdown or reversing one or more 0 the screws at one side or the other ofthe median line of the vessel. In a ship the slowing down or even thefailure of one of the owerplants has no more serious effect than t at ofretarding her rogress. the eccentric thrust of the screws eing easilycounter-acted by the rudder.

In other tpes of vehicles however, and more particu arly in airplaneswhich depend on their powerplants for sustentation as well as forwardspeed, tl e'defective functioning of any of the powerplants is a muchmore serious matter which may, and often does, entail disastrousconsequences.

Several types of airplanes are at present being operated in whichthe'motive power is furmshed by a plurality of powerplants, eachactuating its individual propeller independently from the others; the,powerplants with their propellers being usually arranged symmetricallywith reference .to the length axis of the machine, so that the resultanttractive effort coincides with this axis so long as the individualtractive efi'o'rts of all the propulsion means remain equal. Shouldthese tractive efforts vary individually, the machine would evince atendency to veer toward the side of the least tractive effort and woulddeviate from its intended course; this deviation would have to becounter-acted by the rudder. Thus, maintaining a straight course in theevent of an imperfect functioning of any of the laterally installedpowerplants with an attendant decrease of the power out- Although at thepresent-day aero-motors" have been developed to a high degree ofperfection, yet they are not infallible and still reqliiiire the skilland knowledge of an expert to eep them in running order, and trouble mayarise from a variety of sources.

A plurality of powerplants will give complete satisfaction when theresultant tractive effort coincides at all times with the median line ofthe machine; a satisfactory solution of the problem may be found in thecombination of a plurality of powerplants, each capable of functioningindependently from the others and jointly as well as individuallyadapted to actuate an adjustable propeller, the axis of rotation ofwhich coincides with the fore-and-aft axis of the machine.

This arrangement can be extended by providing the airplane with groupsof engines, each group actuating its own propeller, the en ine groupsthen taking the place of the in ividual engines now used in themultimotor planes.

' The use of a plurality of engines is of particular value inlong-distance flight, when the initial weight of the fuel may be such asto require the combined power of all engines. The fuel consumptionduring the first stage of the trip being necessarily considerable, theweight will diminish rapidly until the use of one of the engines can bedispensed with. Thejourney can then be continued with only part of theavailable powerplants in actual operation.

It may also befound advantageous to use each engine onl part of the timerequired for the trip, an keep one engine in reserve for emergencies, Adifferent combination of engines would then be in operation in alternatesuccession, thus reducing the wear per engine and aflording theopportunity to inspect such engine or engines which are temporarily outof combination.

Emergencies may arise which demand the instant use of all enginescombined andthe emergency may be of such a nature as to make itimperative that this combination be put in operation without loss oftime.

Since all en ines actuate but asingle propeller, it is evi ent that inshunting from one amount of power to another the forward speed of themachine will be materiall affected and that a propeller ofcharacteristics designed for a given speed and horsepower will not beable to do itself justice under the greatlyvarying conditions imposedupon it. It will therefore be necessary to adjust the propeller as todiameter and pitch in 'acof the operator, for in an emergency the matter of a few seconds delay may spell disaster. The pull at a lever andthe turning of a wheel should accomplish the desired result andthereafter the mechanism should require no further attention on the partof the operator,

who should then be able to direct his efforts to the inspection of theengine or engines which have just been shunted outof action.Furthermore, the transmission of power from the various engines to thecommon shaft must be contrived in such a way that a variation in thespeed of any ofthe individual engines does in no way interfere With thenormal functioning of any of the others. Unce the powerplant withtransmission and propulsion means has been adjusted for a desiredcombination, it should be impossible for anyone to change thecombination by inadvertently touching a lever or gras ing a controlwheel, which might occur or instance during a sharp bank in the case ofan airplane or 1n a heavy sea in the case of a vessel. The controlmechanism therefore should be proof against accidental disarrangementand at all times ready for service at'the selection of the operator.

In the case of an airplane, the checking of the landing speed is adesirable feature and the transmission mechanism should thereforepreferably include means whereby the action of the propulsion eans canbe reversed.

Since itis moreover commendable to avoid an unnecessary multiplicity ofparts and to reduce the number and nature of the manip ulations to beremembered by the operator to a minimum, the reversal of-the propulsionmeans should be effected in a manner similar to that of the otheroperations, and by means of the same mechanism.

The above outlined problems and requirements have been duly consideredand the ways and means in and by which they have been i solvedconstitute my invention.

The drawings present an illustration of the invention as applied to acombination of three powerplants. From the description it will beevident that the invention can be adapted to any number ofpowerplantsand that I do not limit myself to three. The

powerplants may be internal combustion engines, steam engines, electricmotors, tur- 6 bines,' wind turbines, jet-propulsion plants or I shallrefer simply as engines, provided withthe self-starters 6, 7 and 8respectively, are anchored to frame d which is secured to the structuralmembers of fuselage 275. Engine 1 has thecrankshaft extension 1 carryingthe spurgear l meshing with the spurgear 1 on the shaft 1 mounted in thedifferential gear box 9. Fig. 2 represents a detailed View of thetransmission housing 9 in which a modification of the transmission fromengine I is shown by shaft 1, which is supported in bearing 1, andcarries bevel pinion 1 meshing with bevelgear rotatably mounted on shaft1; Supported in the bearing 11, engine H has the crankshaft extension10, which carries the bevelge'ar 12 meshing with bevelgear 13 on shaft2. The shaft 2 is rotatable in bearing 14: and in bearing 2* of thedifferential gear housing 9.

Fig. 2 shows a modification of this arrangement, the shaft 2 and thebearing2 being here shown at the opposite side of the gear housing.Shaft 2 has the bevel pinion 2 meshing with the bevelgear 2 mounted freeon the sleeveshaft 2 The sleeveshaft 2 is rotatably mounted on the shaft1..

Enginellll has the crankshaft extension 15 which is supported in bearing16 and carries the bevelgear 17 meshing with bevelgear 18 secured onshaft 3. Shaft 3 is rotatable in bearing 19 and in bearing 3 of the gearhousing 9. Shaft 3 carries the bevelgear 3 in mesh with bevelgear 3which is rotatably mounted on the sleeveshaft 3 The sleeve shaft 3 isrotatably mounted on shaft 2. On shaft 1 issecure'd the sungear 1 whichby the planetgears .1 associates with the sungear 2secured on shaft 2 Onshaft 3 is secured the sungear 3 which by means of the planetgears 3associates with the power transmitting sungear 20. The hub 21 of sungear1 has bearing in the hub 22 of the sungear 20 which actuates the powerdelivery shaft 23. In thedrawing the power delivery shaft is showndirectly connected to the sungear 20. It is understood however,

that any suitable transmission means may be interposed between these.two elements and that I dov not limit myself to the particularconstruction shown in Fig. 2.

Shaft 1 is supported in the bearing 24 of i spider shafts secured in thespider frame 31 and in the annular bearing 32 journaled i g on the ballbearing race 33 mounted on shaft 1.

Gear case 9 contains a Suitable lubricating and heat-absorbing fluid 540which by the pump 541 is forced through the ducts 542 and 543 to theheader 5440f the oil-cooler 545. From the header 544 the fluid passesthrough the thin copper tubes 546 to the header 541 and returns bv wavof the duct 5-1S t o the -g;ear case 9. Water from the radiator 549circulates between the copper tubes 546 and thus reduces the temperatureof the v means of gearing,

- lubricating fluid. The oil pump 541 can be driven by the powerdelivery shaft 23 by or a chain transmission can be employed such assprocket 550 on the power shaft driving sprocket 551 on the pumpshaft555 by means of the chain 552. An alternative means for driving theoilpump is represented by the propeller 553 mounted on shaft 554 whichby clutch 556 run he put in driving relation to pumpshaft The continuousforced circulation of the lubricating fluid through the oil-coolerprevents overheating of all bearings and journals of the differentialtransmission. It is also understood that revision has been made toprevent or minimize leakage'of the lubricating matter through thehearings to the outside and that any of the matter which may escape iscollected and by mechanical means such as pumps and the like, isreturned to the interior of the gearbox. A temperature-indicator,draining cocks and like accessories are also understood to beincorporated in the installation. Anti-friction devices, such asball-bearings and the like .are employed wherever advisable, a few ofwhich are shown in Fig. 2 which represents a crosssection through thedifferential transmission. Shafts 2 and 3 have the reduced section 50 tolessen the friction and the supporting sections 51. and 52 should run onball-bean ings or similar devices. The bearings 27 28 and 29 may beintegral with box 9 or else may be fastened to the bottom thereof bymeans of bolts and the like.

Shaft l 'has slidingly keyed on it the 'clutch A, the face 35 of whichengages with clutchface 34 of bevelgear 1. Clutch A is operated by thelever A turnable on the pivotbearing 44.- On shaft 1 is also slidinglykeyed clutch B, the clutchface 36 of which engages with clutchface 37 ofshaft 2. Clutch B is operated by lever B turnable on the pivotbearing45. Collar 49, fixedly mounted on. the shaft 1, separates clutches A andB and limits their sition when not engaged. Shaft 2 has slidingly keyedon it clutch C, the clutchfa c'etz 39 of which enages with clutch face38 of bevelgear 2..

on pivotbearing 46. Shaft 2 has also slidn y keyed on it clutch D theface 40 of which engages with the clutch face 41 of shaft 3. Clutch D isoperated by lever D turnable on ivotbearing 47.

Shaft 3 lies slidingly keyed to it clutch E theface 43 of which engageswith clutchface 42 of bevelgear 3. Clutch E is operated by lever Eturnable on pivotbearing 48.

For a system of three en nes, designated by I, II, and III respective y,the following combinations are possible:

I and II running in unison, III at rest.

I and III running in unison, II at rest.

II and III running in unison, I at rest.

I, II and III runnin in unison.

I running, II and I I at rest.

II running, I and III at rest.

III running, I and II at rest.

The position of the clutches for these combinations is as follows :For Iand II running in unison, III at rest, clutch A is shifted to the left,engaging bevelgear 1 and thus actuating shaft 1 and sungear 1. Clutch Bis shifted to the left,'shafts 1 and 2 being thus enabled to operateindependently. Clutch C is shifted to the left, engaging bevelgear 2 andactuating shaft 2 and sungear 2. Clutch. D is thrown to the right thuslocking shaft 2 with shaft 3. Clutch E is shifted to the right,disengaging bevelgear 39 from shaft 3. Sungears 2 and 3 rotate' inunison at the same R. P. M. as shaft 2 and since planet gears 3 and 1are journaled on the same spidershafts 30, they will turn in unisonabout the axis of the sungears, and through the planet gears 3 lockingwith sungear 20 will cause the power delivery shaft 23 to turn at thesame speed as shaft 1 For I and III running in unison, II being at rest,clutch A is shifted to the left, an gaging with bevelgear 1 and thusactuating shaft 1' and sungear 1. Clutch B is shifted to the right,locking shaft 1 with shaft 2.

Clutch C is shifted to the right, disengaging bevelgear 2 from shaft 2.Clutch D is shifted to the left allowin relative rotation between shafts2 and 3. lutch E is shifted to the left in enga ement with bevelgear 3,thus actuating sha 3 and sungear 3. Sungears 1 and 2 are thus lockedtogether and rotate in unison, and the resultant R. P. M. of shaft 23will then be twice that of sungear 1 minus'that of 3.

' For II and III runnin in unison with I at rest, clutch A is shi ted tothe right,

thus disengaging bevelgear1 from shaft 1. Clutch B is shifted to theright locking shaft shaft 2 and'sungear 2. Clutch D is shifted to theleft, allowing relative rotation between shafts 2 and 3. Clutch E isshifted to the left and engages bevelgear 3. with shaft 3,

thus actuating sungear 3. The relative speeds of shaft 23 then is thesame as in the previous case.

For I, II and III running in unison, clutch A is shifted to the left, asare also clutches .C and E. Clutches B and D are also shifted to theleft, allowing relative rotation between the three shafts 1 2 and 3 Theradial spider shafts then turn around the axis of the transmissionshafts at a rate equal to half the sum of the R. P. M. of the 'sungears1 and 2. The resultant R. P. M. of shaft 23 is then equal to the R. P,M.- of the sungears 1 and 2 minus the R. P. M. of sungears 3.

For engine I runnirTg, engines II and III being both at rest, clutch Ais shifted to the left, and clutch B is shifted to. the right, lockingshafts 1 and 2. Clutch C is shifted to the ri ht. Clutch D is shifted tothe right thus loc ing shafts 2 and 3 and clutch E is also shifted tothe right. The three shafts are thus locked together and the power fromshaft 1 is transmitted to sungear 20 by the locked differentials.

For engine II running, engines I and III being both at rest, clutch A isshifted to the right, shaft 1 is locked with shaft 2 by shifting clutchB to the right, clutch C is shifted to the left, thus engaging bevelgear2 with shaft 2 and actuating sungear 2; clutch D is shifted to the rightlocking shafts 2 and 3 and clutch E is sifted to the right. The powerfrom shaft 2 is then transmitted to the propeller shaft by the lockeddiifer-' ential as in the preceding case.

For engine III running, engines I and II being both at rest, clutch A isshifted to the right, clutch B is shifted to the right, thus lockingshafts i and 2; clutch C is shifted to the right; clutch D is shifted tothe right locking shafts 2 and 3 and clutch E is shifted to the leftengaging bevelgear 3 with shaft 3, thus actuating sungear 3". The

power of shaft 3 is then transmitted to the propeller shaft bythe lockeddifferentials as in both preceding cases.

From the above it is apparent that a great many combinations in theposition of the clutches are likely to be called for. These positionsare tabulated as follows:

Clutch I and II I and III II and III 1 I and II and III A Left LeltRight Left Left? 1 R R L C Left R Y L L D Right L. A L L E Right L L LIn order to facilitate the shunting from one combination of engines toanother and make this operation largely automatic, a special control hasbeen devised which obviates the chances of error on the part of theoperator, and by means of which the required change of combination canbeeifected in a minimum of time.

The cylindrical frame collectively designated by 54 (Fig.3) is fixedlymounted on the hollow shaft 55 rotatable in the bearing rod 61 and havethe lugs 66 which are 351 tened by bolts or the like to the arms 67 ofrings 68, which are slidably mounted on shaft 55 Rings 68 have the lugs69 to which are pivotally connected the arms of the bellcranks 70pivoted on pin 71 at the end of brackets 72 of the spider ring 73fixedly mounted on shaft 55. The arms 74 of the bellcranks 70 arepivotally connected with the lugs 75 of racks 76 which are slidablyguided in the slots 77 of the end plates 78. The end plates 78 havefixed mounting on the hollow shaft 55 and are connected by the spacerbars 79, thus forming a cylindrical frame rotatable with shaft 55. Forthe sake of brevity the cylindrical frames are hereinafter referred toas drums.

The rod 61 can be moved in the direction of the arrow by means of theforked'lever 80 pivotally connected to the lug 81 of the cylindricalstub 82 which is revol'vably held in the recess 83 of the cap 84 screwedor otherwise suitably fastened on rod 61. V

The racks 7 6, provided with the fingers 85, are normally retracted sothat the said'fingers do not protrude beyond the circumference of thedrum. By moving the rod 61 in the direction of arrow, the bell-cranks 70cause the racks to move outward, thus making the fingers protrudeoutwardly beyond the circumference of the drum..

The cylindrical frame or drum collectively designated by the numeral 86is in all respects similar to the one designated by 54 and has the endplates 94, connected by spacer bars,

fixedly mounted on the hollow shaft 87 which slidably receives the rod92 actuated by the lever 93. The drum 86 has the movable racks I n mLeft R a v n a R R L n a a R a n n is supported by means of the supports102.

